类型安全标准查询，JPA 2.0的新功能：路径未知？

Question

When starting a new Java EE (maven) web app in jbdevstudio there is already some code included, inclusive a Member model with Registration. In the MemberRepository class there two methods which use criteria queries this way:

public Member findByEmail(String email) {
    CriteriaBuilder cb = em.getCriteriaBuilder();
    CriteriaQuery<Member> criteria = cb.createQuery(Member.class);
    Root<Member> member = criteria.from(Member.class);
    // Swap criteria statements if you would like to try out type-safe criteria queries, a new
    // feature in JPA 2.0
    // criteria.select(member).where(cb.equal(member.get(Member_.name), email));
    criteria.select(member).where(cb.equal(member.get("email"), email));
    return em.createQuery(criteria).getSingleResult();
}

public List<Member> findAllOrderedByName() {
    CriteriaBuilder cb = em.getCriteriaBuilder();
    CriteriaQuery<Member> criteria = cb.createQuery(Member.class);
    Root<Member> member = criteria.from(Member.class);
    // Swap criteria statements if you would like to try out type-safe criteria queries, a new
    // feature in JPA 2.0
    // criteria.select(member).orderBy(cb.asc(member.get(Member_.name)));
    criteria.select(member).orderBy(cb.asc(member.get("name")));
    return em.createQuery(criteria).getResultList();
}

I would like to use (eg try out) the codeline(s) of the suggested type-safe criteria queries, but the compiler has a problem with Member_ . What am I missing here?

Greetings Martin

Answer 1

To use JPA Static Metamodel classes in Criteria queries you have to first CREATE the static metamodel classes. All JPA providers include a way of doing it, and their documentation would tell you how that is done. The link here shows it for one